The EF 24-105mm f/4L IS USM Lens from Canon is a versatile, easy-to-use standard zoom lens that covers a focal range from wide-angle to portrait-length telephoto. Its constant maximum aperture of f/4 provides effective consistency when at the telephoto end of the zoom range. The L-series is Canon's flagship professional lens series, combining the highest standards of precision optics and operability with dust and moisture resistant construction. Canon's ring-type Ultrasonic Motor (USM) provides silent and quick autofocus as well as full-time manual focus override. Optical image stabilization enables up to 3-stops of compensation against the effects of camera shake and one Super-UD and three aspherical lens elements minimize aberrations for overall optical clarity. With impeccable construction and comfortable handling, this is a durable yet sophisticated lens that meets the demands of advanced amateur photographers and professional photographers alike. Image Stabilizer great for handheld work, IS Optical Image Stabilizer allows use of shutter speeds up to 3-stops slower with no perceptible increase in image blur. Fixed Aperture With no change in aperture over the full focal length range, photographers can set exposure at the widest aperture and zoom through to 105mm without slowing shutter speed. Super UD and Aspherical Lens Elements Constructed with one Super-UD glass element and three aspherical lenses, this lens minimizes chromatic aberration and distortion. The result is excellent picture quality, even at wide apertures. Ring USM Ring USM (Ultrasonic motor) uses ultrasonic frequency vibrations to drive responsive, near-silent high speed auto focus. Good holding torque stops the focusing lens group with precision without overshoot. Full time manual focus override is available without having to switch out of AF. Super Spectra Coatings Optimized Super Spectra lens coatings and lens element shaping suppress flare and ghosting - more prone to occur with digital cameras due to reflection off the image sensor. Coatings also help achieve true color balance and increase contrast for vivid hi-fidelity